x11: Move X event handling out of the message-pump.

ash/accelerators/accelerator_dispatcher_linux.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ash/accelerators/accelerator_dispatcher.h"
+
+#include "base/memory/scoped_ptr.h"
+#include "base/run_loop.h"
+#include "ui/events/event.h"
+#include "ui/events/platform/platform_event_dispatcher.h"
+#include "ui/events/platform/platform_event_source.h"
+#include "ui/events/platform/scoped_event_dispatcher.h"
+
+#if defined(USE_X11)
+#include <X11/Xlib.h>
+#endif
+
+namespace ash {
+
+namespace {
+
+#if defined(USE_OZONE)
+bool IsKeyEvent(const base::NativeEvent& native_event) {
+  const ui::KeyEvent* event = static_cast<const ui::KeyEvent*>(native_event);
+  return event->IsKeyEvent();
+}
+#elif defined(USE_X11)
+bool IsKeyEvent(const XEvent* xev) {
+  return xev->type == KeyPress || xev->type == KeyRelease;
+}
+#else
+#error Unknown build platform: you should have either use_ozone or use_x11.
+#endif
+
+scoped_ptr<ui::ScopedEventDispatcher> OverrideDispatcher(
+    ui::PlatformEventDispatcher* dispatcher) {
+  ui::PlatformEventSource* source = ui::PlatformEventSource::GetInstance();
+  return source ? source->OverrideDispatcher(dispatcher)
+                : scoped_ptr<ui::ScopedEventDispatcher>();
+}
+
+}  // namespace
+
+class AcceleratorDispatcherLinux : public AcceleratorDispatcher,
+                                   public ui::PlatformEventDispatcher {
+ public:
+  AcceleratorDispatcherLinux()
+      : restore_dispatcher_(OverrideDispatcher(this)) {}
+
+  virtual ~AcceleratorDispatcherLinux() {}
+
+ private:
+  // AcceleratorDispatcher:
+  virtual scoped_ptr<base::RunLoop> CreateRunLoop() OVERRIDE {
+    return scoped_ptr<base::RunLoop>(new base::RunLoop());
+  }
+
+  // ui::PlatformEventDispatcher:
+  virtual bool CanDispatchEvent(const ui::PlatformEvent& event) OVERRIDE {
+    return true;
+  }
+
+  virtual uint32_t DispatchEvent(const ui::PlatformEvent& event) OVERRIDE {
+    if (IsKeyEvent(event)) {
+      ui::KeyEvent key_event(event, false);
+      if (MenuClosedForPossibleAccelerator(key_event)) {
+        XPutBackEvent(event->xany.display, event);
+        return ui::POST_DISPATCH_QUIT_LOOP;
+      }
+
+      if (AcceleratorProcessedForKeyEvent(key_event))
+        return ui::POST_DISPATCH_NONE;
+    }
+
+    ui::PlatformEventDispatcher* prev = *restore_dispatcher_;
+    return prev ? prev->DispatchEvent(event)
+                : ui::POST_DISPATCH_PERFORM_DEFAULT;
+  }
+
+  scoped_ptr<ui::ScopedEventDispatcher> restore_dispatcher_;
+
+  DISALLOW_COPY_AND_ASSIGN(AcceleratorDispatcherLinux);
+};
+
+scoped_ptr<AcceleratorDispatcher> AcceleratorDispatcher::Create(
+    base::MessagePumpDispatcher* nested_dispatcher) {
+  return scoped_ptr<AcceleratorDispatcher>(new AcceleratorDispatcherLinux());
+}
+
+}  // namespace ash